Is possible to create a batch from adobe photoshop 5.5 and use a command line to execute? I need easy batch like "open and save in another kind of extension" but can't find the solution to automate the process from command line.

It sounds like droplets are exactly what you need. Droplets turn any action into an executable that can be run from the command line passing files to process as arguments. Just make the action you described, and go to go to file > automate > create droplet in photoshop to make the droplet.